misc: Move l2tp to plugin

Type: refactor

Change-Id: Ifb36eeb146b87e9e305881429d32d6879e955e1e
Signed-off-by: Neale Ranns <nranns@cisco.com>

1 files changed, 235 insertions, 0 deletions

diff --git a/src/plugins/l2tp/encap.c b/src/plugins/l2tp/encap.c
new file mode 100644
index 00000000000..fbb5fc6ea46
--- /dev/null
+++ b/src/plugins/l2tp/encap.c
@@ -0,0 +1,235 @@
+/*
+ * encap.c : L2TPv3 tunnel encapsulation
+ *
+ * Copyright (c) 2013 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <vppinfra/error.h>
+#include <vppinfra/hash.h>
+#include <vnet/vnet.h>
+#include <vnet/ip/ip.h>
+#include <vnet/ethernet/ethernet.h>
+#include <l2tp/l2tp.h>
+
+/* Statistics (not really errors) */
+#define foreach_l2t_encap_error					\
+_(NETWORK_TO_USER, "L2TP L2 network to user (ip6) pkts")	\
+_(LOOKUP_FAIL_TO_L3, "L2TP L2 session lookup failed pkts")      \
+_(ADMIN_DOWN, "L2TP tunnel is down")
+
+static char *l2t_encap_error_strings[] = {
+#define _(sym,string) string,
+  foreach_l2t_encap_error
+#undef _
+};
+
+typedef enum
+{
+#define _(sym,str) L2T_ENCAP_ERROR_##sym,
+  foreach_l2t_encap_error
+#undef _
+    L2T_ENCAP_N_ERROR,
+} l2t_encap_error_t;
+
+
+typedef enum
+{
+  L2T_ENCAP_NEXT_DROP,
+  L2T_ENCAP_NEXT_IP6_LOOKUP,
+  L2T_ENCAP_N_NEXT,
+} l2t_encap_next_t;
+
+typedef struct
+{
+  u32 cached_session_index;
+  u32 cached_sw_if_index;
+  vnet_main_t *vnet_main;
+} l2tp_encap_runtime_t;
+
+extern vlib_node_registration_t l2t_encap_node;
+
+#define NSTAGES 3
+
+static inline void
+stage0 (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_buffer_t * b)
+{
+  vlib_prefetch_buffer_header (b, STORE);
+  CLIB_PREFETCH (b->data, 2 * CLIB_CACHE_LINE_BYTES, STORE);
+}
+
+static inline void
+stage1 (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_buffer_t * b)
+{
+  l2tp_encap_runtime_t *rt = (void *) node->runtime_data;
+  vnet_hw_interface_t *hi;
+
+  u32 sw_if_index = vnet_buffer (b)->sw_if_index[VLIB_TX];
+  u32 session_index = rt->cached_session_index;
+
+  if (PREDICT_FALSE (rt->cached_sw_if_index != sw_if_index))
+    {
+      hi = vnet_get_sup_hw_interface (rt->vnet_main, sw_if_index);
+      session_index = rt->cached_session_index = hi->dev_instance;
+      rt->cached_sw_if_index = sw_if_index;
+    }
+
+  /* Remember mapping index, prefetch the mini counter */
+  vnet_buffer (b)->l2t.next_index = L2T_ENCAP_NEXT_IP6_LOOKUP;
+  vnet_buffer (b)->l2t.session_index = session_index;
+
+  /* $$$$ prefetch counter... */
+}
+
+static inline u32
+last_stage (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_buffer_t * b)
+{
+  l2t_main_t *lm = &l2t_main;
+  vlib_node_t *n = vlib_get_node (vm, l2t_encap_node.index);
+  u32 node_counter_base_index = n->error_heap_index;
+  vlib_error_main_t *em = &vm->error_main;
+  l2tpv3_header_t *l2tp;
+  u32 session_index;
+  u32 counter_index;
+  l2t_session_t *s;
+  ip6_header_t *ip6;
+  u16 payload_length;
+  u32 next_index = L2T_ENCAP_NEXT_IP6_LOOKUP;
+
+  /* Other-than-output pkt? We're done... */
+  if (vnet_buffer (b)->l2t.next_index != L2T_ENCAP_NEXT_IP6_LOOKUP)
+    return vnet_buffer (b)->l2t.next_index;
+
+  em->counters[node_counter_base_index + L2T_ENCAP_ERROR_NETWORK_TO_USER] +=
+    1;
+
+  session_index = vnet_buffer (b)->l2t.session_index;
+
+  counter_index =
+    session_index_to_counter_index (session_index,
+				    SESSION_COUNTER_NETWORK_TO_USER);
+
+  /* per-mapping byte stats include the ethernet header */
+  vlib_increment_combined_counter (&lm->counter_main,
+				   vlib_get_thread_index (),
+				   counter_index, 1 /* packet_increment */ ,
+				   vlib_buffer_length_in_chain (vm, b));
+
+  s = pool_elt_at_index (lm->sessions, session_index);
+
+  vnet_buffer (b)->sw_if_index[VLIB_TX] = s->encap_fib_index;
+
+  /* Paint on an l2tpv3 hdr */
+  vlib_buffer_advance (b, -(s->l2tp_hdr_size));
+  l2tp = vlib_buffer_get_current (b);
+
+  l2tp->session_id = s->remote_session_id;
+  l2tp->cookie = s->remote_cookie;
+  if (PREDICT_FALSE (s->l2_sublayer_present))
+    {
+      l2tp->l2_specific_sublayer = 0;
+    }
+
+  /* Paint on an ip6 header */
+  vlib_buffer_advance (b, -(sizeof (*ip6)));
+  ip6 = vlib_buffer_get_current (b);
+
+  if (PREDICT_FALSE (!(s->admin_up)))
+    {
+      b->error = node->errors[L2T_ENCAP_ERROR_ADMIN_DOWN];
+      next_index = L2T_ENCAP_NEXT_DROP;
+      goto done;
+    }
+
+  ip6->ip_version_traffic_class_and_flow_label =
+    clib_host_to_net_u32 (0x6 << 28);
+
+  /* calculate ip6 payload length */
+  payload_length = vlib_buffer_length_in_chain (vm, b);
+  payload_length -= sizeof (*ip6);
+
+  ip6->payload_length = clib_host_to_net_u16 (payload_length);
+  ip6->protocol = IP_PROTOCOL_L2TP;
+  ip6->hop_limit = 0xff;
+  ip6->src_address.as_u64[0] = s->our_address.as_u64[0];
+  ip6->src_address.as_u64[1] = s->our_address.as_u64[1];
+  ip6->dst_address.as_u64[0] = s->client_address.as_u64[0];
+  ip6->dst_address.as_u64[1] = s->client_address.as_u64[1];
+
+
+done:
+  if (PREDICT_FALSE (b->flags & VLIB_BUFFER_IS_TRACED))
+    {
+      l2t_trace_t *t = vlib_add_trace (vm, node, b, sizeof (*t));
+      t->is_user_to_network = 0;
+      t->our_address.as_u64[0] = ip6->src_address.as_u64[0];
+      t->our_address.as_u64[1] = ip6->src_address.as_u64[1];
+      t->client_address.as_u64[0] = ip6->dst_address.as_u64[0];
+      t->client_address.as_u64[1] = ip6->dst_address.as_u64[1];
+      t->session_index = session_index;
+    }
+
+  return next_index;
+}
+
+#include <vnet/pipeline.h>
+
+VLIB_NODE_FN (l2t_encap_node) (vlib_main_t * vm,
+			       vlib_node_runtime_t * node,
+			       vlib_frame_t * frame)
+{
+  return dispatch_pipeline (vm, node, frame);
+}
+
+
+/* *INDENT-OFF* */
+VLIB_REGISTER_NODE (l2t_encap_node) = {
+  .name = "l2tp-encap",
+  .vector_size = sizeof (u32),
+  .format_trace = format_l2t_trace,
+  .type = VLIB_NODE_TYPE_INTERNAL,
+  .runtime_data_bytes = sizeof (l2tp_encap_runtime_t),
+
+  .n_errors = ARRAY_LEN(l2t_encap_error_strings),
+  .error_strings = l2t_encap_error_strings,
+
+  .n_next_nodes = L2T_ENCAP_N_NEXT,
+
+  /*  add dispositions here */
+  .next_nodes = {
+    [L2T_ENCAP_NEXT_IP6_LOOKUP] = "ip6-lookup",
+    [L2T_ENCAP_NEXT_DROP] = "error-drop",
+  },
+};
+/* *INDENT-ON* */
+
+#ifndef CLIB_MARCH_VARIANT
+void
+l2tp_encap_init (vlib_main_t * vm)
+{
+  l2tp_encap_runtime_t *rt;
+
+  rt = vlib_node_get_runtime_data (vm, l2t_encap_node.index);
+  rt->vnet_main = vnet_get_main ();
+  rt->cached_sw_if_index = (u32) ~ 0;
+  rt->cached_session_index = (u32) ~ 0;
+}
+#endif /* CLIB_MARCH_VARIANT */
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */